Piecing together your prostate cancer puzzle.

Was this Decipher analysis based off your diagnostic needle biopsy sample or off of tissue taken from radical prostatectomy?

I had a Decipher run on both and the GRID results were dramatically different; there was almost no concordance in the gene expression percentiles between the two reports. You'd think it were two different patients with two different tumors, the results were that unalike.

I discussed this with oncologists at a couple COEs and both said that Decipher is vulnerable to tumor heterogeneity. Because it's testing the phenotypic expression of mRNA and not actually doing DNA sequencing of the tumor tissue, it's apparently more prone to inconsistency than genotype-based somatic analysis. (As aside, you can get true somatic genotype analysis performed on a post-RP tumor sample, but it's a much more intensive process than running a Decipher test and most cancer centers do not typically do this for the majority of patients. I did have such analysis done by MSK after my RP because I had certain aggressive histological markers that they felt warranted the somatic testing.)

My takeaway was that this is why the GRID data is still widely regarded as being of limited clinical/therapeutic value and more for research purposes only. I would caution against drawing too confident a conclusion about your tumor characteristics from anything in this report, especially if it came from a needle biopsy.

@notpetecrowarmstrong

Thanks for your informative comment!

Tumor heterogeneity makes sense in that even a biopsy with multiple positive cores usually has differing Gleason scores, as in my case.

The gene expression chart is from one of my tumors taken from a Gleason 3+4 core (of which I had two), while another 5 Gleason 3+3 cores were not tested.

As I said, all this data represents additional puzzle pieces of information….maybe I was overly optimistic regarding “more than half” of the puzzle pieces being missing.😉

It seems all characterization techniques suffer from ambiguity.

In my case, serial mpMRI’s indicated that my three originally observed lesions (PIRADS 3,4 & 5), two of which were initially identified (via targeted biopsy) as Gleason 3+3, turned out to be invisible in later mpMRI scans. My urologist indicated they were most likely “just inflammation” which resolved.

Probably the most frustrating aspect to the entire PCa prognostication process is when one finds out that the “puzzle picture” has morphed (to continue the analogy).

I’m aware of the limitations of Decipher testing and analysis, as I’m also aware of mpMRI’s and biopsy pathology interpretation ambiguities.

At the end of the day, we all make a risk based decision, based on as much clinical, biomarker, somatic genomic, germline genetic and any other data we can get our hands on.

That said I believe the Decipher information is important, when combined with all the other more routinely obtained information.

I think it, at least, pushes the decision towards more confidence regarding a particular treatment or active surveillance decision.

I also believe this information will only get more useful as the research continues.

Best!

@handera Well said. I also believe Decipher testing is still very valuable and think more guys should take advantage of it if they can. And I was eager myself to dive into my GRID report and try to understand what it implied about my tumor characteristics and the implications for further treatment in the event of BCR. But then my experience with the differing GRID results between my pre-RP and post-RP samples, and the POVs of those two oncologists, softened my zealousness for drawing conclusions at that level of specificity.

I'm still very glad to have my GRID data in hand for reference, such as it is, and the macro-level risk scores are still important (those two numbers happened to be nearly identical for me despite the underlying gene expression differences).

Fascinating article, bud! So PTEN is a really big factor in this whole grab bag of possibilities…and it’s not inherited, but acquired. It is not a death sentence but will definitely prevent ADT alone from controlling the progression.
So far they don’t know how or why, but they have a drug for it…damn, the head literally spins trying to stay current with this disease….thanks for the article👍
Phil

"Puzzle" is the perfect word to use. There are so many pieces to PC. Every person is different and doctors should handle each case differently, not based on standard of care guidelines.

Pin cushion or SOC. Where do you fall? In my experience, it comes down to how much time and research YOU put in to your decision. I cringe at hearing cases where someone blindly agrees with everything a urologist says. It’s a merry go round. The URO is a SURGEON and their SOC is almost always removal of the prostate. Robotics have made the local community hospital based URO basically “competent” in taking the prostate out. That said, a highly qualified technician is probably more likely to do a better job. We are fortunate (if you call Prostate Cancer fortunate) that there are multiple modalities to treat PCa. Just 20 plus years ago the accepted SOC was removal of the prostate. Sadly, the rate is still too high, but the light is shining more every year, and educated men are asking for 2nd and 3rd opinions instead of relying only on the urologist to have their prostates removed. But, during that 20 years another specialty has emerged as the preeminent science in fighting this disease…radiation oncologists. Thankfully taking away the large source of income from urologists taking prostates out. Hormone deprivation also commands a large cash cow with billions of dollars of revenue. Confusing patients if 2-3 years of taking ADT and the serious side effects are worth destroying your QOL for a 4-5% increase in 15 year survival rate. It’s not funny anymore, that you will probably die from something else before PCa. It’s not a secret how I feel about the state of treatments in fighting PCa. To answer my initial question—Yes, I would prefer being a pin cushion rather than a lemming falling off the cliff for what a urologist says is the standard of care.

@heavyphil

Mark Perloe (retired MD), author of the article, was diagnosed with PCa in March 2020 and decided on MRI guided SBRT after a PMSA PET scan found evidence of metastatic disease.

He spends time advocating and supporting men diagnosed with PCa.

He called me (I had no connection except through a support group) a couple years ago, just to provide information and his experience regarding various aspects of MRI guided SBRT, when I was investigating this particular treatment type.

Dr Perloe is an amazingly intelligent physician with a kind heart towards helping PCa men in his retirement!
https://www.uclahealth.org/news/story/radiation-treatment-proves-be-answer-doctor-with-prostate

@handera “He learned that the cancer had started to spread to other parts of his body”…
It’s a nice promo for MRIdian, which I also looked into in 2019; and it’s best used for a 5 treatment ‘real time’ regimen superior (as far as tissue margins) to Cyberknife. Also used for spot metastases.
Did he discuss ADT with you, or how many sessions he had? I’m curious only because metastatic disease is no walk in the park, as the article (highlighting Dr Kishan) seems to imply.
But again, I understand it was an attempt to educate men on the disease and show that it strikes doctors as well.
Good guy to know!
Phil

I also wsnted to dork off about the Decipher Grid with the two radiologists I spoke to. They both shut it down very quickly, telling me not to read too much into it. Sure enough, it says that it is only for research purposes.

@notpetecrowarmstrong Interesting, but was your overall score similar?